Me and me Dad managed to fit one of the Calibra 8.1 litre intercoolers behind the Cav Turbo front bumper. It means you have to loose the fog lights and also a lot of chopping behind the bumper is needed. You also have to move the oil cooler to up behind the grill like the Astra GTE's and the P/S pipes under the crossmember but most importantly it does fit.
It took us about a day and half in all, but obviously the first one always takes the longest as you have to see what needs doing as you go sort of thing. Once done and fitted there is still about an inch or more on the bottom scoop before the IC front, so it still looks really nice.
I did take some pictures but have no way of uploading em
It certainly is easier to fit in the Calibra as me old man found out when fitting his phase 3